RESUMEN
The salinosporamides are potent proteasome inhibitors among which the parent marine-derived natural product salinosporamide A (marizomib; NPI-0052; 1) is currently in clinical trials for the treatment of various cancers. Methods to generate this class of compounds include fermentation and natural products chemistry, precursor-directed biosynthesis, mutasynthesis, semi-synthesis, and total synthesis. The end products range from biochemical tools for probing mechanism of action to clinical trials materials; in turn, the considerable efforts to produce the target molecules have expanded the technologies used to generate them. Here, the full complement of methods is reviewed, reflecting remarkable contributions from scientists of various disciplines over a period of 7 years since the first publication of the structure of 1.
Asunto(s)
Inhibidores Enzimáticos/farmacología , Lactonas/farmacología , Inhibidores de Proteasoma , Pirroles/farmacología , Animales , Diseño de Fármacos , Fermentación , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Tecnología Farmacéutica/métodosRESUMEN
Large-scale fermentation of the marine actinomycete Salinispora tropica for production of salinosporamide A (NPI-0052; 1) clinical trials materials provided crude extracts containing minor secondary metabolites, including salinosporamide B (2) and a new congener, 3. Spectroscopic characterization revealed that 3 is identical to antiprotealide, a molecular hybrid of 20S proteasome inhibitors 1 and omuralide (4) not previously described as a natural product. Analysis of crude extracts from shake flask cultures of three wild-type S. tropica strains confirmed the production of antiprotealide at 1.1, 0.8, and 3.0 mg/L. Thus, antiprotealide is a natural product metabolite of S. tropica.
Asunto(s)
Actinobacteria/química , Productos Biológicos/química , Productos Biológicos/aislamiento & purificación , Lactamas/química , Lactamas/aislamiento & purificación , Lactonas/química , Lactonas/aislamiento & purificación , Pirroles/química , Pirroles/aislamiento & purificación , Animales , Productos Biológicos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Concentración 50 Inhibidora , Lactamas/farmacología , Lactonas/farmacología , Biología Marina , Estructura Molecular , Complejo de la Endopetidasa Proteasomal , Pirroles/farmacología , ConejosRESUMEN
The discovery of the anticancer agent salinosporamide A (NPI-0052) resulted from the exploration of new marine environments and a commitment to the potential of the ocean to yield new natural products for drug discovery and development. Driving the success of this process was the linkage of academic research together with the ability and commitment of industry to undertake drug development and provide the resources and expertise to advance the entry of salinosporamide A (NPI-0052) into human clinical trials. This paper offers a chronicle of the important events that facilitated the rapid clinical development of this exciting molecule.
Asunto(s)
Antineoplásicos/química , Descubrimiento de Drogas , Lactonas/química , Pirroles/química , Drogas en Investigación , Estructura MolecularRESUMEN
A series of chlorinated bisindole pyrroles, lynamicins A-E (1-5), was discovered from a novel marine actinomycete, NPS12745, which was isolated from a marine sediment collected off the coast of San Diego, California. Close to full length 16S rRNA sequence analysis indicated that NPS12745 is a novel strain of a recently described marine actinomycete with the proposed genus name Marinispora. The antimicrobial spectrum of these compounds was evaluated against a panel of 11 pathogens, which demonstrated that these substances possess broad-spectrum activity against both Gram-positive and Gram-negative organisms. Significantly, compounds 1-5 were active against drug-resistant pathogens such as methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecium.
Asunto(s)
Actinobacteria/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Hidrocarburos Clorados/aislamiento & purificación , Hidrocarburos Clorados/farmacología , Indoles/aislamiento & purificación , Indoles/farmacología , Pirroles/aislamiento & purificación , Pirroles/farmacología , Actinobacteria/genética , Antibacterianos/química , California , Farmacorresistencia Bacteriana/efectos de los fármacos , Enterococcus faecium/efectos de los fármacos , Hidrocarburos Clorados/química , Indoles/química , Biología Marina , Resistencia a la Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Pirroles/química , Staphylococcus aureus/efectos de los fármacos , Resistencia a la Vancomicina/efectos de los fármacosRESUMEN
We recently described the development of a potassium-chloride-based salt formulation containing low sodium concentration (5.0 mM) to support the growth of Salinispora tropica strain NPS21184 and its production of salinosporamide A (NPI-0052). In order to determine whether the above low-sodium salt formulation can also support the growth of other S. tropica strains, we examined the growth of the type strain CNB440 and the parent strain CNB476, from which strain NPS21184 was derived as a single colony isolate. We demonstrated that good growth rate and yield of S. tropica strains CNB440 and CNB476, similar to S. tropica strain NPS21184 reported earlier, were detected in both agar and liquid media containing the potassium-chloride-based salt formulation with sodium concentration of 5.0 mM. Furthermore, we also detected good growth rate and yield of all three S. tropica strains on potassium-sulfate-based salt formulation agar medium containing both low-sodium (5.7 mM) and low-chloride (14 mM) content. This finding confirms the observation that the species of S. tropica does not have a seawater growth requirement but requirement for a specific combination of salts to provide a balance of salts and maintain a high enough ionic strength for growth.
Asunto(s)
Medios de Cultivo/química , Medios de Cultivo/metabolismo , Micromonosporaceae/crecimiento & desarrollo , Micromonosporaceae/metabolismo , Agua de Mar/microbiología , Cloruro de Sodio/metabolismo , Lactonas , Micromonosporaceae/aislamiento & purificación , PirrolesRESUMEN
In order to improve aqueous solubility of nocathiacin I (1), a potent antibacterial agent, N-demethylation of the amino-sugar moiety was sought. Irradiation of 1 in DMF/CH(2)Cl(2) with UV light of 380 nm led to a cyclic product 2, which was hydrolyzed to yield the desired nocathiacin VI (3). Treatment of 1 with shorter UV light caused trans-cis isomerization of a c-c double bond.
Asunto(s)
Oxígeno/química , Péptidos/química , Antiinfecciosos/farmacología , Química Farmacéutica/métodos , Diseño de Fármacos , Hidrólisis , Péptidos y Proteínas de Señalización Intercelular , Luz , Metilación , Modelos Químicos , Estructura Molecular , Oxidación-Reducción , Solubilidad , Solventes/química , Relación Estructura-Actividad , Rayos UltravioletaRESUMEN
A novel marine actinomycete strain NPS8920 produces a new class of 4-oxazolidinone antibiotics lipoxazolidinone A, B and C. Lipoxazolidinone A possesses good potency (1-2 microg/mL) against drug-resistant pathogens methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium (VRE). Strain NPS8920 exhibits different morphologies in both agar and submerged cultures. The ability of strain NPS8920 to sporulate on saline-based agar media but not on deionized water-based agar medium supported that strain NPS8920 is a marine actinomycete. While strain NPS8920 does not require seawater for growth, the production of lipoxazolidinones by strain NPS8920 can only be detected in the seawater-based media. The optimal production of lipoxazolidinones was observed in the natural seawater-based medium. Strain NPS8920 produced 10-20% of lipoxazolidinones in the synthetic sea salt Instant Ocean-based medium and no production in the sodium chloride-based and deionized water-based media.
Asunto(s)
Actinobacteria/crecimiento & desarrollo , Actinobacteria/metabolismo , Antibacterianos/metabolismo , Oxazolidinonas/metabolismo , Agua de Mar/microbiología , Medios de Cultivo/química , Estructura MolecularRESUMEN
Salinosporamide A (NPI-0052) is currently produced by a marine actinomycete, Salinispora tropica, via a saline fermentation process using a non-defined, commercially available synthetic sea salt, Instant Ocean. In order to control the consistency of the production of NPI-0052 and related analogs, two chemically defined salt formulations were developed to replace Instant Ocean. A chemically defined sodium-chloride-based salt formulation with similar sodium and chloride contents as in Instant Ocean was found to support higher production of NPI-0052 and a better metabolite production profile for downstream processing than Instant Ocean. A chemically defined sodium-sulfate-based salt formulation with low chloride concentration at 17 mM was found to support a similar NPI-0052 and metabolite production profile as Instant Ocean. The sodium-sulfate-based formulation is a robust formulation for large-scale production process due to its reduced corrosiveness in fermentation as compared with the saline fermentation utilizing Instant Ocean or the sodium-chloride-based salt formulation. The production of NPI-0052 in both chemically defined salt formulations was successfully scaled-up to a 42-l fermentor, indicating that these salt formulations can be used for large-scale manufacturing process.
Asunto(s)
Medios de Cultivo/química , Lactonas/metabolismo , Micromonosporaceae/metabolismo , Pirroles/metabolismo , Cloruro de Sodio/metabolismo , Sedimentos Geológicos/microbiología , Microbiología Industrial , Lactonas/química , Espectrometría de Masas , Micromonosporaceae/crecimiento & desarrollo , Pirroles/química , Cloruro de Sodio/análisisRESUMEN
In this paper, we described the development of a potassium-chloride-based-salt formulation containing low sodium concentrations (5.0 to 11 mM) to support the growth of Salinispora tropica strain NPS21184 and its production of salinosporamide A (NPI-0052). The sodium present in the media was essentially derived from the complex nitrogen sources Hy Soy, yeast extract, and peptone used in the media. We demonstrated that good growth rate and yield of S. tropica strain NPS21184 were detected in both agar and liquid media containing the potassium-chloride-based-salt formulation with sodium concentration as low as 5.0 mM, significantly less than the critical seawater-growth requirement concentration of 50 mM sodium for a marine microorganism. We also observed good production of NPI-0052 (176 to 243 mg/l) by S. tropica strain NPS21184 grown in production media containing the potassium chloride-based-salt formulation. The production of deschloro analog, salinosporamide B (NPI-0047), was significantly lower in the low-sodium-salt-formulation medium than in the high-sodium-salt-formulation media. We demonstrated that while S. tropica strain NPS21184 is a novel marine actinomycete that requires high salt content for growth, it does not require sodium-chloride-based seawater-type media for growth and production of NPI-0052.
Asunto(s)
Medios de Cultivo/química , Fermentación , Microbiología Industrial , Lactonas/metabolismo , Micromonosporaceae/metabolismo , Pirroles/metabolismo , Compuestos de Sodio/metabolismo , Lactamas/metabolismo , Micromonosporaceae/crecimiento & desarrollo , Agua de Mar/microbiologíaRESUMEN
Marine actinomycete strain NPS008920, a member of the new genus Marinispora, was isolated from a sediment sample collected in Cocos Lagoon, Guam. In natural sea water containing media, the strain produced a series of novel 2-alkylidene-5-alkyl-4-oxazolidinones, lipoxazolidinone A (1), B (2), and C (3). Compounds 1- 3 showed broad spectrum antimicrobial activity similar to that of the commercial antibiotic linezolid (Zyvox), a 2-oxazolidinone. Hydrolysis of the amide bond of the 4-oxazolidinone ring of 1 resulted in loss of antibacterial activity. The 2-alkylidene-4-oxazolidinone represents a new antibiotic pharmacophore and is unprecedented in nature.
Asunto(s)
Actinobacteria/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Oxazolidinonas/aislamiento & purificación , Oxazolidinonas/farmacología , Antibacterianos/química , Guam , Haemophilus influenzae/efectos de los fármacos , Biología Marina , Estructura Molecular , Oxazolidinonas/química , Relación Estructura-ActividadRESUMEN
Addition of acrylic resin Amberlite XAD-7 during the fermentation of Salinispora tropica significantly enhanced the production of NPI-0052 by 69 fold. Examination of the time course of resin addition to the Salinispora tropica fermentation demonstrated that the increase in the production of NPI-052 is due to the stabilization effect by resin but not the removal of an end product feedback repression. Delay in resin addition to the fermentation led to decreases in the production of NPI-0052 to the amounts that are synthesized prior to the resin addition.
Asunto(s)
Resinas Acrílicas/farmacología , Resinas de Intercambio Aniónico/farmacología , Fermentación , Lactonas/farmacología , Micromonosporaceae/metabolismo , Poliestirenos/farmacología , Inhibidores de Proteasas/farmacología , Complejo de la Endopetidasa Proteasomal/metabolismo , Pirroles/farmacología , Apoptosis/efectos de los fármacos , Fermentación/efectos de los fármacos , Humanos , Micromonosporaceae/enzimología , Inhibidores de ProteasomaRESUMEN
During the past 15 years, most large pharmaceutical companies have decreased the screening of natural products for drug discovery in favor of synthetic compound libraries. Main reasons for this include the incompatibility of natural product libraries with high-throughput screening and the marginal improvement in core technologies for natural product screening in the late 1980s and early 1990 s. Recently, the development of new technologies has revolutionized the screening of natural products. Applying these technologies compensates for the inherent limitations of natural products and offers a unique opportunity to re-establish natural products as a major source for drug discovery. Examples of these new advances and technologies are described in this review.
Asunto(s)
Antiinfecciosos , Antineoplásicos , Factores Biológicos , Animales , Antiinfecciosos/química , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/metabolismo , Antiinfecciosos/uso terapéutico , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/uso terapéutico , Bacterias/metabolismo , Factores Biológicos/química , Factores Biológicos/aislamiento & purificación , Factores Biológicos/metabolismo , Factores Biológicos/uso terapéutico , Biotecnología/tendencias , Ensayos Clínicos como Asunto , Enfermedades Transmisibles/tratamiento farmacológico , Evaluación Preclínica de Medicamentos , Hongos/metabolismo , HumanosRESUMEN
Feeding sodium butyrate (0.25-1 mg/ml) to cultures of Salinispora tropica NPS21184 enhanced the production of salinosporamide B (NPI-0047) by 319% while inhibiting the production of salinosporamide A (NPI-0052) by 26%. Liquid chromatography mass spectrometry analysis of the crude extract from the strain NPS21184 fed with 0.5 mg/ml sodium [U-(13)C(4)]butyrate indicated that butyrate was incorporated as a contiguous four-carbon unit into NPI-0047 but not into NPI-0052. Nuclear magnetic resonance analysis of NPI-0047 and NPI-0052 purified from the sodium [U-(13)C(4)]butyrate-supplemented culture extract confirmed this incorporation pattern. The above finding is the first direct evidence to demonstrate that the biosynthesis of NPI-0047 is different from NPI-0052, and NPI-0047 is not a precursor of NPI-0052.
Asunto(s)
Ácido Butírico/química , Lactamas/química , Lactonas/química , Pirroles/química , Lactamas/metabolismo , Lactonas/metabolismo , Espectroscopía de Resonancia Magnética , Micromonosporaceae/metabolismo , Pirroles/metabolismoRESUMEN
We examined the effects of halogens on the production of salinosporamide A (NPI-0052) by the obligate marine actinomycete Salinispora tropica NPS465, specifically the production of analogs containing halogens other than chlorine. Adding NaF, NaBr and NaI directly to the production medium prepared in seawater containing -3% NaCl did not induce the production of the corresponding analogs. Replacing seawater with 2-3% NaI in the production medium enhanced the production of NPI-0052 by 2.1 fold. Replacing seawater with 2-3% NaBr in the production medium suppressed the production of NPI-0052 but induced the production of a brominated analog at very low yield. Using a stepwise enrichment of bromide in the seed cultures in order to reduce the chloride ion carried over to the production medium, the production of the brominated analog was enhanced by 4 fold. We also demonstrated that the growth of this obligate marine actinomycete is dependent upon sodium concentration, not chloride concentration.
Asunto(s)
Actinomycetales/metabolismo , Bromuros/farmacología , Lactonas/química , Lactonas/metabolismo , Pirroles/química , Pirroles/metabolismo , Compuestos de Sodio/farmacología , Fluoruro de Sodio/farmacología , Yoduro de Sodio/farmacología , Actinomycetales/efectos de los fármacos , Actinomycetales/crecimiento & desarrollo , Cromatografía Líquida de Alta Presión , Medios de Cultivo/química , Lactonas/aislamiento & purificación , Estructura Molecular , Pirroles/aislamiento & purificaciónRESUMEN
Salinosporamide A (NPI-0052; 3), a highly potent inhibitor of the 20S proteasome, is currently in phase I clinical trials for the treatment of cancer. During the course of purifying multigram quantities of 3 from Salinispora tropica fermentation extracts, several new salinosporamides were isolated and characterized, most of which represent modifications to the chloroethyl substituent at C-2. Specifically, 3 was isolated along with the known compound salinosporamide B (4), the previously undescribed methyl congener salinosporamide D (7), and C-2 epimers of 3 and 7 (salinosporamides F (9) and G (10), respectively). Salinosporamide I (13), in which the methyl group at the ring junction is replaced with an ethyl group, and the C-5 deshydroxyl analogue salinosporamide J (14), were also identified. Replacement of synthetic sea salt with sodium bromide in the fermentation media produced bromosalinosporamide (12), 4, and its C-2 epimer (11, salinosporamide H). In addition to these eight new salinosporamides, several thioester derivatives were generated semisynthetically. IC50 values for cytotoxicity against human multiple myeloma cell line RPMI 8226 and inhibition of the chymotrypsin-like (CT-L) activity of purified rabbit 20S proteasomes were determined for all compounds. The results indicate that thioesters may directly inhibit the proteasome, albeit with reduced potency compared to their beta-lactone counterparts.
Asunto(s)
Actinobacteria/química , Lactonas , Inhibidores de Proteasoma , Pirroles , Actinobacteria/crecimiento & desarrollo , Bahamas , Cristalografía por Rayos X , Concentración 50 Inhibidora , Lactonas/química , Lactonas/aislamiento & purificación , Lactonas/farmacología , Biología Marina , Conformación Molecular , Estructura Molecular , Pirroles/química , Pirroles/aislamiento & purificación , Pirroles/farmacologíaRESUMEN
Recent findings from culture-dependent and culture-independent methods have demonstrated that indigenous marine actinomycetes exist in the oceans and are widely distributed in different marine ecosystems. There is tremendous diversity and novelty among the marine actinomycetes present in marine environments. Progress has been made to isolate novel actinomycetes from samples collected at different marine environments and habitats. These marine actinomycetes produce different types of new secondary metabolites. Many of these metabolites possess biological activities and have the potential to be developed as therapeutic agents. Marine actinomycetes are a prolific but underexploited source for the discovery of novel secondary metabolites.
Asunto(s)
Actinobacteria/metabolismo , Antibacterianos/metabolismo , Antifúngicos/metabolismo , Antineoplásicos/metabolismo , Agua de Mar/microbiología , Actinobacteria/clasificación , Antibacterianos/química , Antifúngicos/química , Antineoplásicos/químicaRESUMEN
Stereoselective reduction of dehydroalanine double bond in nocathiacin I afforded the primary amide 2. Enzymatic hydrolysis of the amide 2 provided the carboxylic acid 3, which upon coupling with a variety of amines furnished amides 4-32. Some of these semi-synthetic derivatives have retained very good antibacterial activity and have improved aqueous solubility.
Asunto(s)
Antibacterianos/síntesis química , Antibacterianos/farmacología , Enterococcus faecalis/efectos de los fármacos , Péptidos/síntesis química , Péptidos/farmacología , Staphylococcus aureus/efectos de los fármacos , Streptococcus pneumoniae/efectos de los fármacos , Antibacterianos/química , Técnicas In Vitro , Péptidos y Proteínas de Señalización Intercelular , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Péptidos/química , Solubilidad , Estereoisomerismo , Relación Estructura-Actividad , Agua/químicaRESUMEN
Natural product compounds are the source of numerous therapeutic agents. Recent progress to discover drugs from natural product sources has resulted in compounds that are being developed to treat cancer, resistant bacteria and viruses and immunosuppressive disorders. Many of these compounds were discovered by applying recent advances in understanding the genetics of secondary metabolism in actinomycetes, exploring the marine environment and applying new screening technologies. In many instances, the discovery of a novel natural product serves as a tool to better understand targets and pathways in the disease process. This review describes recent progress in drug discovery from natural sources including several examples of compounds that inhibit novel drug targets.
Asunto(s)
Bacterias/metabolismo , Productos Biológicos/biosíntesis , Productos Biológicos/química , Evaluación Preclínica de Medicamentos/métodos , Preparaciones Farmacéuticas/aislamiento & purificación , Animales , Bacterias/genética , Productos Biológicos/genética , Preparaciones Farmacéuticas/químicaRESUMEN
The solid-phase synthesis of a library based on the natural product anisomycin is described. The resulting library was tested against a panel of bacterial and fungal targets, and active compounds were identified in a Staphylococcus aureus whole-cell assay and an efflux-deficient fungal whole-cell assay.
Asunto(s)
Anisomicina/química , Antiinfecciosos/síntesis química , Antiinfecciosos/farmacología , Productos Biológicos/química , Técnicas Químicas Combinatorias , Antiinfecciosos/química , Línea Celular , Hongos/citología , Hongos/efectos de los fármacos , Humanos , Concentración 50 Inhibidora , Estructura Molecular , Staphylococcus aureus/citología , Staphylococcus aureus/efectos de los fármacos , Relación Estructura-ActividadRESUMEN
A Streptomyces sp. (NPS008187) isolated from a marine sediment collected in Alaska was found to produce three new pyrrolosesquiterpenes, glyciapyrroles A (1), B (2), and C (3), along with the known diketopiperazines cyclo(leucyl-prolyl) (4), cyclo(isoleucyl-prolyl) (5), and cyclo(phenylalanyl-prolyl) (6). The structures of 1, 2, and 3 were established using spectroscopic methods.